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Poor young African-Americans are most likely to die while receiving dialysis for kidney disease, according to new scientific findings supporting the notion that wealth plays a significant role in health outcomes. But socioeconomics doesn’t entirely explain the racial health disparity, researchers from Albert Einstein College of Medicine say.

Even when considering socioeconomic status, blacks in poor neighborhoods were still 1.5 times more likely than white counterparts in the United States to die while on dialysis. Overall, the disparity for disease incidence rose to 3.4 times higher among African-Americans in a sampling of more than 11,000 study participants across the country.

"In our study, young black patients' risk of death was worse when they lived in poor neighborhoods,” study leader Tanya Johns said in a press statement. “We need to better understand how the wealth of someone's neighborhood affects patients' health while on dialysis.”

Specifically, African-Americans ages 18 to 30 years of age are nearly twice as likely as whites to succumb to kidney failure at younger ages, Johns and her colleagues reported Thursday in the Journal of the American Society of Nephrology. They found that white and black patients receiving dialysis between 2006 and 2009 experienced markedly different survivability rates, with data merged from the U.S. Renal Data System and the U.S. Census Bureau to compare health and wealth.

After a median follow-up of 23 months, investigators discovered that young African-Americans living in poor neighborhoods died at higher rates than other Americans, supporting past study findings. Still, Johns cannot say what else besides wealth lies behind the racial health disparity in dialysis outcomes. The causes of kidney failure, as well as other diseases, were dismissed by the researchers as irrelevant to the racial gap, moreover.

“Among patients residing in low SES [socioeconomic-status] neighborhoods, blacks had greater mortality than whites after adjusting for baseline demographics, clinical characteristics, rurality, and access to care factors,” Johns wrote in the paper. “This difference in mortality between blacks and whites was significantly attenuated in higher SES neighborhoods.”

Acute kidney failure comes as the kidneys become unable to filter waste from the blood, allowing dangerous levels of toxins to accumulate. Some 31 million Americans — 10 percent of Americans — suffer from chronic kidney disease, according to the American Kidney Fund. Past research has shown racial health disparities among diverse groups of Americans relative to whites.